Rush's legal problems are politically motivated. The only protection he receives are from republicans on varying levels. If he loses the support of republicans then he would have no one so he has to be careful not to alienate them.
Rush is not even coming out in support of this ports deal - he simply stated in light of the huge tsunami against it, let's make sure all the CORRECT facts come out - from what I've seen so far, it doesn't seem like a problem to me. Perhaps you know something the 12-agency CFIUS process missed?
He got some "cover" from the ACLU too, don't forget that ; )